This invention relates to a dispense apparatus. It is particularly concerned with beverage dispense apparatus for post-mix beverages, i.e. beverages comprising a diluted concentrate, e.g. a syrup or cola, in which the concentrate is mixed with a diluent, usually water, at the point of dispense.
Accordingly, the present invention provides a beverage dispense apparatus comprising a mixing head in which a concentrate and a diluent may be mixed, means to deliver the diluent and the concentrate separately to the mixing head, an outlet nozzle from the mixing head, and a diluent changeover valve means upstream of the mixing head for selectively connecting the mixing head to a source of a first diluent and a source of a second diluent, and the diluent changeover valve means being positioned adjacent the mixing head.
The first diluent is preferably still water and the second diluent is preferably carbonated water and the invention will for convenience be more specifically described below with references to those diluents. By means of the changeover valve means a choice of carbonated and noncarbonated post-mix beverages may be provided by connecting the required source of diluent to the mixing head through one flow line. Because the changeover valve means is situated close to the mixing head, the amount of one diluent that remains in the flow line between the valve means and the head after a dispense is minimised so that its mixing in with a subsequent beverage dispensed using the other diluent has little or no noticeable effect.
In its simplest form, the apparatus can dispense still or carbonated post-mix beverages using one concentrate. More preferably, the apparatus can dispense a plurality of still or carbonated post-mix beverages using a plurality of concentrates. One or more concentrates may be supplied to the mixing head from its own source by conventional means and is mixed there with either carbonated or still water as required in response to a command signal for a specific beverage. Thus, for example, if an apparatus having a choice of four concentrates is used, a total of eight different beverages may be dispensed utilising only one changeover valve means for the water supply, one mixing head and dispense nozzle and one set of electronic controls including one keypad by means of which the required beverage is ordered for dispense. Of course, there will also need to be means to supply each of the concentrates from its source to the mixing head.
Where more than four concentrate flavors are required, for example six or eight concentrates, it may be found desirable to have two water supply valves, one being dedicated to carbonated water supply and the other having the changeover valve means connectable in turn to a source of carbonated water and to a source of still water. As the majority of beverages dispensed are normally carbonated, two changeover valve means will not normally be required. This apparatus may also conveniently have two mixing heads, each with its own nozzle, and two sets of electric controls and keypads rather than dispensing a large number of different beverages by means of a single nozzle and control unit which has less flexibility in operation.
In a preferred arrangement, a water control valve is provided between the mixing head and the changeover valve means. The water control valve is preferably adjustable between open and closed conditions to provide a selected flow. In this way the required amount of water can be supplied to the mixing head by connecting the appropriate water source via the changeover valve means for a pre-determined time. With this arrangement, one water control valve can be employed for both the still and carbonated water supplies, thereby avoiding the cost of separate water control valves, valve adjustment means and, where required a flow meter for each water supply.
The diluent flow control valve is preferably a valve of the type described in International patent application no. PCT/GB98/03564 (WO99/29619), which application is incorporated herein by reference thereto. The particular flow control valeincludes a substantially rigid housing containing a passageway between an inlet and an outlet of the valve and a closure member moveable in the passageway from a first position in which the valve is fully closed to a second position in which the valve is fully open. The wall of the passageway or the closure member define at lease one groove, having a transverse cross-section that increases in area in the downstream or upstream direction of flow. In this way, movement of the closure member from the first, closed position towards the second, open position opens a flow channel through the groove the area of which varies according to the position of the closure member to adjust the flow. The groove(s) may be, for example, of tapering V-shape and will, for convenience, hereafter be referred to as xe2x80x9cV-groovesxe2x80x9d and the valves of this general type as xe2x80x9cV-groove valvesxe2x80x9d, although it will be appreciated that the grooves may, if desired, have a different tapering cross-section, e.g. of circular, rectangular or other shape.
The progressive increase or decrease in area of the groove flow channels can produce excellent linear flow through these V-groove valves, i.e. for a given pressure the flow rate is more directly proportional to the valve position than for conventional valves. This enables better control of the flow rate over the entire operating range of the valve. The water control valve, particularly when it is a V-groove valve, is preferably provided with a setting mechanism in the form of a stepper motor, e.g. of the pulsed magnetically driven type, whereby the water control valve may be set to an appropriate opening for the required dispense. Alternatively, a lever mechanism, a proportional solenoid actuator or a diaphragm operated mechanism may be used to set the water control valve to the required position.
The concentrate control valves may be any suitable type of valve which the skilled person will readily be able to determine for the concentrates being used. For example, a simple on/off valve that automatically closes on losing power, e.g. with solenoid valve control. The changeover valve means may be, for example, a solenoid valve or a spool valve or any other suitable valve that may be connected in turn to one or other of the diluent supply sources.
A flow meter, e.g. a flow turbine, may be connected into the diluent supply line, preferably downstream of the changeover valve means so that only one meter is required for both diluents. If desired, a flow meter may also be positioned in each concentrate flow line. The flow meter or meters may then be connected to a control means pre-programmed to allow a certain volume or time of flow for each beverage to be dispensed. The control means, when a particular required dispense is signalled, will also open the control valves to the desired degree, monitor the flow and then shut off the valves when the necessary amount of dispense has taken place.
When the water control valve is a V-groove valve as described above, the control means preferably delays the opening of the concentrate control valve for a short period until its opening of the V-groove valve has allowed the closure member of that valve to reach the desired position.
In the event of a power failure or other fault during a dispense, as indicated above, the preferred concentrate control valve will close automatically. Where the water control valve is a V-groove valve, a battery power back-up system may be required in order to close the valve. Alternatively, and more preferably, instead of the battery back-up, the changeover valve means may be arranged to close automatically if a power failure or other fault arises during dispense. Thus, when the changeover valve means comprises two solenoid valves, one for the still water and the other for the carbonated water, whichever diluent is flowing through its respective open solenoid valve when a power failure occurs, that valve will shut off to stop flow although the V-groove control valve will remain open.
The apparatus of the invention also enables carbonated beverages to be dispensed having a range of carbonation levels. This is achieved by using the changeover valve means to dispense first one of the diluents and then the other diluent. The proportion of mixed diluents in the beverage can be varied over the whole range from 100% carbonated water to 100% still water.